Unidentified Network issue in Windows 7 x64 - AGAIN

This problem is driving me insane, I swear. I'd fixed it once, but now its back to haunt me and I have no idea what causes it. It's just so random.

I've posted a thread about it here before, but had managed to fix the problem. What I did to get rid of it was:
1. Set "Speed & Duplex" in my adapter properties to a fixed speed (in my case it was 10 Mbit Half-Duplex, the others didn't work).
2. Changed network speed (WAN port speed) in my router from 10/100 Mbit Auto to fixed "100 Mbit".

That seemed to have done the trick and everything worked for 2 weeks. Today I go out for lunch for 30 minutes and when I come back the connection is gone. I reset the adapter - nothing. I've tried all the regular stuff again, reinstalled the drivers etc., reset the router/laptop but it still can't find the network.

It's a disaster as this is my work laptop and I have to be online all the time. What on Earth could've happened while I was out? The laptop was locked (and I always have it locked whenever I leave it) so it's absolutely impossible that somebody had messed with my settings.

I've checked - the router & adapter settings are still the same but for some reason the settings that had worked for 2 weeks don't work now anymore. I'm going mad.

The problem persists in safe mode and I've tried every Speed&Duplex setting now - nothing works anymore. The adapter doesn't seem to be absolutely dead as it recognises the cable, but still can't get on the network.

Please help me.

Here is a full list of my adapter settings. Any idea what may have caused it to die during sleep in locked mode?

Hello,

Can you do an 'ipconfig /all' please.

Do you have the latest installed drivers? Has Windows updated the drivers whilst you where out?


Dave

No, I just checked - the latest update was on March the 2nd. I have the latest drivers available on the Realtek website. My Nvidia and internal controller drivers are also up to date.

What kills me is that I've had this problem already and had gotten rid of it once. And now it's back even though nothing has changed. Usually with issues like this there at least some sort of logic, but this problem just seems to come and go randomly. The fix I'd used for it last time doesn't seem to work anymore and I don't get it how this can be possible.

Here is my ipconfig /all:

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:\Users\Alex>ipconfig/all

Windows IP Configuration

Host Name . . . . . . . . . . . . : Alex-PC
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
Physical Address. . . . . . . . . : E8-11-32-C0-99-CB
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::1408:4d8:e88a:288a%27(Preferred)
Autoconfiguration IPv4 Address. . : 169.254.40.138(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . :
DHCPv6 IAID . . . . . . . . . . . : 468193586
DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-16-CE-75-AF-E8-11-32-C0-99-CB

DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
fec0:0:0:ffff::2%1
fec0:0:0:ffff::3%1
NetBIOS over Tcpip. . . . . . . . : Enabled

Tunnel adapter Teredo Tunneling Pseudo-Interface:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter isatap.{2A09569C-B7C4-4D53-A23F-7A7C3CE754CC}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #3
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Here are my adapter settings:

ARP Offload - Enabled
Auto Disable Gigabit - Disabled
Energy Efficient Ethernet - Enabled
Flow Control - Enabled
Green Ethernet - Enabled
Interrupt Moderation - Enabled
IPv4 Checksum Offload - Rx & Tx Enabled
Jumbo Frame - Disabled
Large Send Offload v2 (IPv4) - Enabled
Large Send Offload v2 (IPv6) - Enabled
Network Address - Not Present
NS Offload - Enabled
Priority & VLAN - Priority & VLAN Enabled
Receive Buffers - 512
Receive Side Scaling - Enabled
Shutdown Wake On Lan - Enabled
Speed & Duplex - 10 Mbit Half Duplex
TCP Checksum Offload (IPv4) - Rx & Tx Enabled
TCP Checksum Offload (IPv6) - Rx & Tx Enabled
Transmit Buffers - 128
UDP Checksum Offload (IPv4) - Rx & Tx Enabled
TCP Checksum Offload (IPv6) - Rx & Tx Enabled
Wake on Magic packet - Enabled
Wake on pattern match - Enabled
WOL & Shutdown Link Speed - 10 Mbps First

I've tried various combinations, but this is how they normally look - the default settings that I'm back to now. The only thing different is Speed & Duplex setting (used to be Auto-Negotiation). Right now I can change it to anything and the network is still unrecognised.

I have tried enabling/disabling the device, removing it from the system completely (with the driver) and installing from scratch - the problem still remains.

You're getting an IP address in the 169.254.x.x APIPA block. This means the network connection isn't getting as far as getting an address from your LAN's DHCP server. In this case, "unidentified network" is a symptom of DHCP failure rather than the reason your network connection won't work.

DHCP working OK for other computers on the network?

What happens if you assign your computer a static IP address?

Have you tried using a different cable to connect your system to a different port on your router (or switch)?

The fact that it worked when you forced speed to 10mbit suggests a problem with your cabling, NIC, or the port on your router/switch.

Everything else is working fine in the network. We've never had a problem like that in about 2 years that we've had this router. Normally when someone new comes to the office (business trip, meeting etc.) they just plug their computer to the socket and connect immediately. I may recall a couple times people had to reset their laptops to get connection, but that's it.

I'm not sure how to assign a static IP. Do you mean setting a Network Address in adapter properties? I've tried that (seen suggestions online), but no success. I've tried using a different cable, no luck either.

How to assign a static IP:
How to Assign a Static IP Address in XP, Vista, or Windows 7 - How-To Geek

How many devices are connected to your network? Check your routers DHCP scope to see if you are giving the correct amount of addresses out.

Change the Speed and Duplex to Auto again - You shouldnt have to change this really. When did the problem start again? Was it after or before the 2nd March? - If it was after you may want to roll back the driver.


Dave

So now I've been playing around with settings again (I've been doing it for the last 2 days whenever I have a free moment at work).

1. I went to Power Management and disabled the "Allow the computer to turn off this device to save power" thingy.
2. I have disabled QoS Packet Scheduler, Kaspersky Anti-Virus NDIS Filter and TCP/IPv6.

And it found a network. And lost it 5 minutes later. Here is my ipconfig/all after it connected.
The thing is - it had lost the network right after I'd plugged the laptop into the power outlet. It might be a coincidence, but last time the network died it was also somehow related to power management - I went out to lunch, locked the laptop, it went to sleep and when I woke it up - the network was gone.

Can anybody see any pattern here? Maybe suggest some adapter settings that might be screwing things up?
I don't need any power management optimisations TBH - 90% of the time my laptop is not working on battery supply. I'd be fine with disabling all of them.

Here is the ipconfig/all from when it got the network:

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:\Users\Alex>ipconfig/all

Windows IP Configuration

Host Name . . . . . . . . . . . . : Alex-PC
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
Physical Address. . . . . . . . . : E8-11-32-C0-99-CB
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IPv4 Address. . . . . . . . . . . : 192.168.0.103(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : 7 марта 2012 г. 14:01:51
Lease Expires . . . . . . . . . . : 14 марта 2012 г. 14:01:50
Default Gateway . . . . . . . . . : 192.168.0.1
DHCP Server . . . . . . . . . . . : 192.168.0.1
DNS Servers . . . . . . . . . . . : 192.168.0.1
NetBIOS over Tcpip. . . . . . . . : Enabled

Wireless LAN adapter Wireless Network Connection 3:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter #
2
Physical Address. . . . . . . . . : DC-A9-71-1E-50-2E
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes

Wireless LAN adapter Wireless Network Connection 2:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter
Physical Address. . . . . . . . . : DC-A9-71-1E-50-2E
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes

Wireless LAN adapter Wireless Network Connection:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . : Dlink
Description . . . . . . . . . . . : Intel(R) Centrino(R) Wireless-N 130
Physical Address. . . . . . . . . : DC-A9-71-1E-50-2D
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter isatap.{20768159-9323-42DC-9B54-C0DA83476810}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter Teredo Tunneling Pseudo-Interface:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes
IPv6 Address. . . . . . . . . . . : 2001:0:4137:9e76:24ee:f5dd:a42c:82fd(Pref
erred)
Link-local IPv6 Address . . . . . : fe80::24ee:f5dd:a42c:82fd%13(Preferred)
Default Gateway . . . . . . . . . : ::
NetBIOS over Tcpip. . . . . . . . : Disabled

Tunnel adapter isatap.Dlink:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #2
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter isatap.{2A09569C-B7C4-4D53-A23F-7A7C3CE754CC}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #3
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

Tunnel adapter isatap.{F6DE66B8-01C3-4A50-B33B-4BA90D52E91A}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Microsoft ISATAP Adapter #4
Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0
DHCP Enabled. . . . . . . . . . . : No
Autoconfiguration Enabled . . . . : Yes

It's back to Unidentified network now and doing the same thing doesn't help at all. I'm even more confused now. The right solution seems to always be just inches away. I can't figure out any pattern for this.

Bumping for help.

1. The static IP trick didn't help.
2. I got more hints to this problem being power-related now. I've just seen the following happen: I came to work, plugged in the LAN cable, laptop found the network, laptop lost the network in a while. I disabled the adapter, unplugged the power cable, enabled the adapter and it found the network again. The same thing didn't work while the power cable had been plugged.

I have disabled Green Ethernet and Energy Efficient Ethernet in the adapter settings, but the problem still remains when the laptop is plugged in. What else can be the issue here?

"When did the problem start again? Was it after or before the 2nd March?"

From my previous post.


Dave